Circuit-controlling key.



HfE. SHREEVE. CIRCUIT CONTROLLING KEY.

APPLICATION FILED 001212, 1911.

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Patented May 14, 1912..

H. E. SHREEVE:

CIRCUIT GONTROLLING KEY. APPLIOATION 1111111) 0013.12. 1911.

Patented May 14, 1912.

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UNITED STATES PATENT OFFICE.

HERBERT E. SHREEVE, OF MILBURN, NEW JERSEY, ASSIGNOR TO WESTERN ELECTRICCOMPANY, OF NEW YORK, N. Y., A CORPORATION OF ILLINOIS.

CIRCUIT-CONTROLLING KEY.

This invention relates to circuit controlling apparatus and has for itsobject to pro vide a switching key for establishing or maintainingcertain circuit conditions and for varying the current conditions in anyparticular circuit.

More specifically` this invention relates to a key structure embracing aplurality of sets of contact springs and a spring-actuating membertherefor capable of being moved in two directions, its position in onedirection of its movement determining the particular group of contactsprings with which it will engage, while its movement in a direction atan angle to the first mentioned line of movement, while in a particularposition brings it into engagement with the contact springs of the groupcorresponding to that particular position. For example, the sets ofcontact springs may be of different lengths and arranged in a horizontalrow and the actuating member therefor adapted to be moved in a verticaldirection to a position where it may be moved horizontally intoengagement with the sets of springs of a particular length.

One of the features of this invention is the means provided for lockingthe springactuating member against movement in one direction except whenit is in a particular position of its other movement with respect to thesets of contact springs.

Other features of this invention are the structural details andcombinations of parts as will hereinafter more fully appear.

In the drawings-Figure l is a view in side elevation with parts insection of a key embodying this invention; Fig. 2 is a view similar toFig. l with parts of the key in operated position; Fig. 3 is a plan viewof the key shown in Figs. l and 2; Fig. 4 is a transverse sectional viewtaken upon line 4 4 of Fig. 2 showing the key and parts with the plungerin its upper posit-ion; Fig. 5 is the same as Fig. 4 with the plunger inits lower position; Fig. 6 is a detail perspective view of a part of thekey structure;

Specification of Letters Patent.

Application led October 12, 1911.

Patented May 14, 1912.

Serial No. 654,279.

Fig. 7 is a circuit diagram illustrating the key of this invention inconnection with a telephone repeater circuit.

As shown in the drawings, 5 designates a base or supporting memberprovided between its ends with raised or projecting members 6, 6 formingan upwardly opening channel 7 adapted to receive a longitudinallymovable block 8. The lower face of the base 5 is provided with a slot 9which opens into the channel 7 and has secured thereto an insulatingplate l0 which has a corresponding slot ll in alinement with the slot 9in said base. Located near the opposite ends of said block 3 areinsulating strips 12, l2 which are secured thereto by means of studs 13,13 projecting downwardly through the alined slots 9 and l1 of the base 5and plate l0, and are provided with heads 14, 14 adapted to slide alongthe lower face of the plate l0. The strips l2, l2 rest upon the lowerpart of the channel 7 and provide an insulated sliding surface for theblock 8.

Reciprocally supported in the block S is a plunger rod 20, the lower endof which projects downwardly through the alined slots 9 and l1 and theupper end of which projects upwardly through a slot 2l in an insulatingplate 22 secured to the upper portion of said base 5. Secured to thelower end of the plunger rod 2O is a spring-actuating block 25. Thisblock is formed of insulating material and is reciprocally mounted uponguide rods 26, 2G secured at their upper ends to the longitudinallymovable block 8 andA have secured to their lower ends antifrictionrollers 27, 27 which engage a groove 28 in a frame member 29.Surrounding said rods 26, 26 are coiled springs 30, 30, the lower endsofwhich rest upon collars or washers 31, 3l upon said rods and the upperends of which are in engagement with the lower face of saidspring-actuating block. The frame member 29 is secured to the base 5 bymeans of posts 32, 32. Mounted upon the upper end of the plunger rod 2Ois a key cap 35.

Mounted upon the frame member 29 and insulated therefrom and from eachother are a plurality of sets of spring contact members 40, 4l, 42, 43and 44, the contact between each set of springs being closed by theengagement of the block 25 with one spring of the set. The set ofsprings 40 is shorter than the remaining sets and is adapted to.

be engaged by the block 25 only when said block is in its lower positionor level as shown in dotted lines in Figs. 1 and 2. rl`he other sets ofsprings, however, will be actuated in either level, and the block 25being of uniform width throughout its length will retain each set ofsprings actuated in its actuated position as it is moved from one set tothe other. The block 25 may be provided near its advancing end withnotched portions 45, 45 which, as they are brought into engagement withthe succeeding springs will tend to retard the movement of said blockand this retardation will be perceptible to the hand of the operator. Anindex may be provided upon the tace of the plate 22 to indicate whichset of springs is in engagement with one of the notches.

In its application to certain circuits it is necessary that provision bemade to prevent the actuating block moving from one vert-ical positionor level to the other while the said block is in any position of itslongitudinal movement, except its normal or starting position, where itis out of engagement with all of the springs. The structure by means otwhich the key is made to meet this requirement is as follows: Secured tothe plunger rod 20 are two collars 50 and 51 which are separated adistance slightly greater than the combined thickness ot' the lowermember of the base 5 and the insulating plate 10. rlhe collar 50 issmaller in diameter than the collar 51 and there is provided in the base5 and the plate 10 adjacent one end of the alined slots therein acircular opening 52 which is slightly smaller in diameter than thecollar 51, but is of large enough diameter to permit the collar 50 topass therethrough. r1`he said collar 50, however, is larger in diameterthan the width ot the slots 9 and 11 and the plunger rod can thereforeonly be reciprocated to move the block 25 into its lower position orlevel when the collar 50 is opposite the opening 52. Thus it will beseen by reference to Figs. 4 and 5 that when the block 25 is to be movedlongitudinally of the key and into engagement with the spring sets 41,42, 43 and 44, the collar 50 will be within the channel 7, while thecollar 51 will be in engagement with the lower tace of the plate 10.When, however, the block 25 is moved to its lower level to engage thespring set 40, the collar 50 will pass through the opening 52 and willengage the lower tace of the plate 10 as it is moved into engagementwith the successive spring sets.

In Fig. 7 in which the key of this invention is illustrated as appliedto a telephone repeater circuit 59 and 60 are the main wires of atelephone line and 61 and 62 the primary and secondary windings of anoutput repeating coil. rlhe winding 62 is included in the line wire 59and from a central point in this winding and bridged across the linewires 59 and 60 is condenser 63 in series with one winding of an inputrepeating coil comprising the windings 64, 65. rFhe winding 65 is in alocal circuit which includes condensers 66, 66 and is adapted to beconnected through either back or front contacts 68, 68 or 69, 69 of arelay 70 with a receiver winding 71 of a repeater. The primary winding61 ot the output repeating coil has one ot its terminals connectedthrough resist-ance coils 72, 73, 74 controlled by the sets of springs41, 42, 43 and 44 with a grounded battery 75, the other terminal of saidprimary being connected with the repeater transmitter button 76. A localcircuit is also provided from the transmitter button 76 and amagnetizing winding 77 as follows: from the grounded battery 75 contactsprings 41, 42, 43 and 44, primary winding 61, conductor 79, stationaryelectrode of carbon button 76, carbon granules 80, the vibratoryelectrode of said button, conductor 81, winding 77 through impedancecoil 83 to ground. The portion of this circuit which includes winding 77and the impedance coil 83 is shunted by means of a condenser 85. Thefunction of the impedance coil 83 is to limit the flow of current inthis circuit and. that of the condenser 85 to localize the microphoniccurrents in the transmitter button and exclude such currents from themagnetizing winding 77. The winding of the relay is connected with thegrounded battery through the set of contact springs 40. Thus byoperating the key with the block 25 in its upper position or level theamount of current admitted to the transmitter button circuit can beregulated while the movement of the block 25 in its lower position willreverse the polarity ot the receiver winding through the operation ofthe relay 70 and also regulate the amount ot current in the transmitterbutton.

l,What I claim is 1. In a switch key, the combination with a pluralityof sets of contact springs, ot a spring-actuating member for saidsprings adapted to be moved .in two directions, said actuating memberhaving a plurality of preliminary positions in one direction of itsmovement and being adapted to be brought into engagement with saidswitch springs when moved in a diiierent direction and while in any oneof its preliminary positions.

2. 1n a switch key, the combination with a plurality of set-s of contactsprings, of a spring-actuating member adapted to be moved in twodirections, said member having a plurality of preliminary positions inone direction ot its movement and adapted to engage said switch springswhen moved in a different direction and while in any of its preliminarypositions, and means for locking said member against movement in thefirst mentioned direction while it is in engagement with said switchsprings.

3. In a switch key structure, the combina tion with a key base, of aplurality of sets of Contact springs, a plunger therefor having aplurality of preliminary positions in a direction at right angles tosaid base, and adapted to be moved in a direction parallel to said baseinto engagement with said springs in any of its preliminary positions.

4L. In a switch key structure, the combination with a key base, of asliding block carried thereby, a reciprocally mounted plunger rodcarried by said block, a spring-actuating member carried by said plungerrod and having a plurality of preliminary positions controlled by saidplunger rod and a plurality of sets of switch springs adapted to beengaged by said actuating member in the movement of said sliding block.

5. In a switch key, the combination with a base, of a longitudinalmovable block mounted in said base, a reciprocally mounted plunger rodcarried by said block, a spring-actuating member carried by said plungerrod and having a plurality of preliminary positions controlled by saidrod, a plurality of sets of switch springs of different lengths adaptedto be engaged by said actuating member, and means for locking saidplunger rod against reciprocation when said actuating member is inengagement with any of said sets of springs.

6. In a switch key, the combination with a base having a longitudinallyarranged channel and being provided with a slot having an enlargedopening adjacent one end thereof, of a rect-angular block adapted toslide in said channel, a reciprocally mounted plunger rod carried bysaid block and extending through said slot, a plurality of sets ofcontact springs, a spring-actuating member carried by said plunger rodand a collar on said plunger rod larger in diameter than said slot butadapted to pass through said enlarged opening.

7 In a switch key, the combination with a base, of a longitudinallymovable block carried by said base, a reciprocally mounted plunger rodcarried by said block, a frame member supported by said base, aplurality of sets of contact springs mounted upon said frame member, aspring-actuating member carried by said plunger, and guide rods for saidspring-actuating member each attached at one end to said sliding blockand having sliding engagement with said frame member at its other end. A

8. In a switch key, the combination `with a base, of a longitudinallymovable block supported in said base, a reciprocally mounted plunger rodcarried by said block, a spring-actuating member carried by said plungerrod, a trame member supported by said base and having a groove therein,guide rods for said spring-actuating block each attached at one end tosaid sliding block, antifriction rollers carried by the opposite ends ofsaid guide rods and engaging the groove in said frame member, andsprings surrounding said frame member and normally tending to force saidspring-actuating member in one direction.

9. In a switch key, the combination with a base having a longitudinallyarranged slot therein and provided adjacent one end of said slot with anenlarged opening, an insulating plate secured to the lower face ot saidbase and having a slot therein in alinen ment with the slot in said baseand an enlarged opening in alinement with the opening in said base, alongitudinally movable block supported by said base, a reciprocallymounted plunger rod carried by said block, and extending through saidalined slots, a spring-actuating member carried by said plunger rod, aplurality of sets of switch springs adapted to be actuated thereby, andtwo collars secured to said plunger rod, one of said collars adapted toengage the lower face of said plate in one position of said plunger rodand the other of said collars being adapted to engage the lower face ofsaid insulating plate in another position of said plunger rod.

10. In a switch key, the combination with a key base, ot a plunger rodhaving both a reciprocal and a longitudinal movement with respectthereto, a plurality of sets of contact springs, a spring-actuatingmember carried by said plunger, said actuating member having a portionwhereby said member is retarded by engagement with said springs, and anindex on said tace for indicating the set of contact springs lastactuated by said plunger.

In vvitness whereof, I, hereunto subscribe my name this 25th day of SeptA. D., 1911.

HERBERT E. sHnEEvE.

Witnesses IRVING MACDONALD, FRANK A. FLEISCHMAN.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents,

Washington, I). C. a

